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Neuronal avalanches are a form of spontaneous activity widely observed in cortical slices and other types of nervous tissue, both in vivo and in vitro. They are characterized by irregular, isolated population bursts when many neurons fire together, where the number of spikes per burst obeys a power law distribution. We simulate, using the Gillespie(More)
We have investigated 3-dimensional brain current density reconstruction (CDR) from intracranial electrocorticogram (ECoG) recordings by means of finite element method (FEM). The brain electrical sources are modeled by a current density distribution and estimated from the ECoG signals with the aid of a weighted minimum norm estimation algorithm. A series of(More)
—Simulations of biologically realistic neurons in large densely connected networks pose many problems to application programmers, particularly on distributed memory computers. We discuss simulations of hundreds of thousands to millions of cells in a model of neocortex in the context of new computing platforms with many tens of thousands to hundreds of(More)
1. Receptor cell activity in the frog's eminentia olfactoria was recorded using metal-filled micro-electrodes. 2. Several units discharged spontaneously with a mean frequency lower than 0.2 spikes per sec, or were silent in periods of up to 5 min. The other units displayed spontaneous activities between 0.2 and 1.05 spikes per sec; their activity could be(More)
A scalable network model intended for study of neocortical epileptiform activity was built on the pGENESIS neural simulator. The model included superÿcial and deep pyramidal cells plus four types of inhibitory neurons. An electroencephalogram (EEG) simulator was attached to the model to validate model behavior and to determine the contributions of(More)
Improved non-invasive localization of the epileptogenic foci prior to epilepsy surgery would improve surgical outcome in patients with partial seizure disorders. A critical component for the identification of the epileptogenic brain is the analysis of electrophysiological data obtained during ictal activity from prolonged intracranial recordings. The(More)
A cross-validation (CV) method based on state-space framework is introduced for comparing the fidelity of different cortical interaction models to the measured scalp electroencephalogram (EEG) or magnetoencephalography (MEG) data being modeled. A state equation models the cortical interaction dynamics and an observation equation represents the scalp(More)
This paper contains an analysis of a simple neural network that exhibits self-organized criticality. Such criticality follows from the combination of a simple neural network with an excitatory feedback loop that generates bistability, in combination with an anti-Hebbian synapse in its input pathway. Using the methods of statistical field theory, we show how(More)
Detection and analysis of epileptic seizures is of clinical and research interest. We propose a novel seizure detection and analysis scheme based on the phase-slope index (PSI) of directed influence applied to multichannel electrocorticogram data. The PSI metric identifies increases in the spatio-temporal interactions between channels that clearly(More)